1. Field of the Invention
The present invention relates in general to gas turbines and more particularly to a gas-turbine power plant of the recuperative type.
2. Description of the Prior Art
An example of a prior art gas-turbine power plant is disclosed in pages 24-25 of "Gas Turbine World: March-April 1987" and also shown in FIG. 7. Referring to the figure, a gas-turbine power plant 41 includes a compressor 42, a combustor 49 and a turbine 43 connected to the compressor 42 by means of a shaft 44 so as to drive a load 46 by way of a reduction gear 45.
A recuperator 47 includes a flow passage 47a for conducting, as indicated by the arrows, high-temperature exhaust gas from the turbine 43 and a flow passage 47b for conducting low-temperature intake air from the compressor 42. The flow passages 47a and 47b are arranged side by side with heat conductive thin-wall therebetween so that the heat of the exhaust gas from the turbine 43 is conducted to the intake air for thereby improving the performance efficiency of the power plant, e.g., the fuel consumption rate.
Such a recuperative type gas-turbine power plant requires a heat insulating material 51 for insulating the combustor 49, the turbine 43 and a duct 50 interconnecting therebetween for attaining a good performance efficiency while at the same time for protecting adjacent parts and elements from the heat of the power plant. Due to this, a space for disposition of the heat insulating material 51 is necessitated, resulting in an increased size of the gas-turbine power plant, an increased number of constitutent parts and therefore an increased assembling and manufacturing cost.